Re: Interop issues regarding tables and css tables

On Thursday 2014-06-12 23:38 -0400, L. David Baron wrote:
> On Thursday 2014-06-12 20:36 +0000, Greg Whitworth wrote:
> > This is a multi-part problem that I'll _try_ to explain succinctly.  We found the following an interop issue[1] where Blink/Gecko set the baseline for text in a table cell at the top when an image is included in the same row. IE sets the baseline as the height of the entire row including the image. To test this behavior further I swapped out the image with another replaced element, this time a generic iframe and now Blink/Gecko offer the same behavior as IE. I would have expected all of these to produce the same result (matching IE's behavior).
> 
> This is explicitly undefined in CSS 2.1, per the sentence:
> 
>   # If such boxes are tall enough, there are multiple solutions and
>   # CSS 2.1 does not define the position of the line box's baseline
>   # (i.e., the position of the strut, see below). 
> 
> in http://www.w3.org/TR/CSS21/visudet.html#line-height .  In other
> words, when an aligned subtree with vertical-align: top or bottom is
> present that is taller than the aligned subtree associated with the
> strut for the block, then the position of the strut for the block
> (and everything aligned to it) is undefined.
> 
> I think when we agreed to make it undefined in 2.1 we may have
> agreed on what we wanted it to be defined as for level 3, but I
> don't remember the details.

The minutes I can find are the discussion of
http://wiki.csswg.org/spec/css2.1#issue-117 in
http://lists.w3.org/Archives/Public/www-style/2010May/0312.html ,
and I don't see any resolution of what behavior we want for that
case.

The discussion of the desired behavior seems to be minuted in:
http://lists.w3.org/Archives/Public/www-style/2009Jun/0184.html
but I don't think it looks like we reached a conclusion.

There was also an earlier resolution to leave it undefined in
http://lists.w3.org/Archives/Public/www-style/2004Feb/0148.html

-David

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                          https://www.mozilla.org/   𝄂
             Before I built a wall I'd ask to know
             What I was walling in or walling out,
             And to whom I was like to give offense.
               - Robert Frost, Mending Wall (1914)